Life and Environmental Sciences and Environmental Systems, University of California, Merced, Merced, CA, 95343, USA.
Hopkins Marine Station, Stanford University, Pacific Grove, CA, 93950, USA.
Environ Microbiol Rep. 2018 Jun;10(3):272-282. doi: 10.1111/1758-2229.12635. Epub 2018 Mar 26.
Respiration of organic material is a central process in the global carbon (C) cycle catalysed by diverse microbial communities. In the coastal ocean, upwelling can drive variation in both community respiration (CR) and the microbial community, but linkages between the two are not well-understood. We measured CR rates and analysed microbial dynamics via 16S rRNA gene sequencing, to assess whether CR correlated with upwelling irrespective of changes in the microbial community, or if the particular microbial community present was a factor in explaining variations in CR. CR varied significantly over time as a function of temperature, dissolved oxygen (DO) and chlorophyll-all of which are altered by upwelling-but also varied with a 'subnetwork' (i.e., a group of microbial taxa that covaried with one another) of the whole community. One subnetwork was associated with higher CR and warmer temperatures, while another was associated with lower CR and DO. Our results suggest that CR in the coastal ocean varies with both environmental variables, and a portion of the microbial community that is not directly correlated with upwelling intensity.
有机物质的呼吸作用是全球碳（C）循环的一个核心过程，由多样化的微生物群落催化。在沿海海域，上升流会导致群落呼吸（CR）和微生物群落的变化，但两者之间的联系尚未得到很好的理解。我们通过 16S rRNA 基因测序来测量 CR 速率并分析微生物动态，以评估 CR 是否与上升流有关，而不考虑微生物群落的变化，或者当前特定的微生物群落是否是解释 CR 变化的一个因素。CR 随时间显著变化，这是温度、溶解氧（DO）和叶绿素变化的结果-所有这些都是上升流引起的-但也与整个群落的“子网”（即与其他微生物分类群相互关联的一组微生物分类群）有关。一个子网与更高的 CR 和更高的温度有关，而另一个子网与更低的 CR 和 DO 有关。我们的结果表明，沿海海域的 CR 随环境变量和与上升流强度没有直接相关性的一部分微生物群落而变化。
